This thesis is a critical ethnographic account of the Wartha people, a small group of hunter-horticulturalists living on the Torassi or Bensbach River, in the southwest corner of the Western Province of Papua New Guinea (PNG). This area is adjacent to the international border between PNG and Indonesias Papua Province (West Papua). Since 1895, the mouth of the Torassi has anchored the southern border between New Guineas colonial territories and their successor states. The Wartha experience of colonial and postcolonial developments has been shaped by their borderland status. Up until the 1960s, the Wartha had sporadic contact with outsiders and virtually no involvement in the cash economy. Subsequent state and capitalist encroachment has often attempted to manage or exploit the areas abundant wildlife, which Wartha have described as our gold. These engagements have led to social disruption, including conflicts over lands and resources, and the erosion of their moral economy. A political ecology perspective is employed to analyse the Wartha relationship with their dynamic, biodiversity-rich savanna environment, and their interaction with wider political and socio-economic systems on a remote, underdeveloped borderland. Past consideration of conservation and development in the area has focused on problems of distance, environment, economic resources, infrastructure and services. I argue that a detailed understanding of core aspects of Wartha societykinship and exchange relations, political leadership, and associated cultural orientations elucidates the nature of articulation with outside others. Contestation over resources, and landscape change, must also be understood with reference to the transboundary region in which these occur, a zone of engagement between two contiguous borderlands, enmeshed within wider polities and biophysical processes. The Wartha live on the periphery of the PNG state, and have limited involvement with wider markets. Nonetheless, articulation with capitalism on an Asia-Pacific borderland has resulted in deleterious social and environmental outcomes; developments that can be explained using a political ecology approach. In so doing, this thesis presents new insights on the Melanesian experience of modernity, and makes an anthropological contribution to the growing literature on border studies.